To play pocket billiards successfully requires two things: (1) knowledge of where to strike the cue and object balls to produce the desired result, and (2) the skill to make the shot correctly. The knowledge is obtained through personal instruction, readily available literature, or experience. However, the present method of adapting that knowledge to practical use on the billiard table consists of trial-and-error reproduction of individual shots. The player does this by "eye-balling" both the desired point of impact between the cue stick and the cue ball, and between the cue ball and the object ball, and then attempting the shot. Because of the variation in "eye-balling" between each shot, that method necessarily requires a great many shots before the player develops the skill to make it properly and consistently. Thus, the skill to make the shot correctly is the result only of a great deal of practice.